A joint arrangement of the abovementioned type is known, for example, from DE 102 53 906 A1. In the joint arrangement described there, the mutually confronting faces of the joint parts carry a toothing with a symmetrical tooth profile. This joint arrangement, as a rule, ensures a reliable hold in the respectively set position of the segments in relation to one another, as long as the tensioning mechanism is effective. In the known embodiment, the tensioning mechanism comprises an eccentric lever which is mounted pivotably on the shaft journal and which, when the eccentric lever is thrown, acts as a tie rod, by means of which the two joint parts are tensioned with their tooth profiles relative to one another. The oblique tooth flanks give rise, at least when the bed segments are subjected to load, to spreading forces which attempt to press the joint parts away from one another. If the tensioning mechanism is not tightened reliably or, for example, the eccentric lever is mistakenly adjusted in the opening direction, there is the risk that the loaded bed segment abruptly swings downwards. This risk is great particularly when the patient's entire weight bears on the respective bed segment.